This decision was brought about, in part, by the fact that Mulvihill was married, and that his wife Theresa had just found out about the affair.

The court heard that, the day before the murder, Mulvihill bought a black hooded jumper and a white plastic chain.

He then secretly travelled to Sydney from the Gold Coast. He then lay in wait for his former lover to come home.

''He had gone to her place that evening ... waited outside for her, followed her up the stairs to her unit, without her knowing, followed her inside the unit and then attacked her,'' Crown prosecutor Maria Cinque told the jury.

Mulvihill's barrister, Kate Traill, said Ms Yeo's death was ''a love story that turned to tragedy''.

She said her client, heartbroken about the end of the affair, had simply come to the apartment to talk but suddenly found himself being attacked with a large, stainless steel kitchen knife.

In the ensuing struggle, Traill said, Yeo was accidentally stabbed twice, at which point Mulvihill fled the scene, ditching the knife and his bloodied hoodie and shoes on the way back to his hotel.

But on Monday, the jury rejected this version, taking less than two hours to reach a unanimous guilty verdict.